Colisión en el aire entre LS 4 y SF 25 durante la aproximación en Hornberg
El 22 de abril de 2000, un planeador LS 4 y un motovelero SF 25 colisionaron durante su aproximación al aeródromo de Hornberg. Ambas aeronaves regresaban de vuelos locales y tenían la intención de aterrizar en la pista 18. El LS 4 volaba delante y ligeramente por encima del SF 25 cuando ocurrió la colisión a pocos metros del suelo. El SF 25 fue destruido al aterrizar tras desviarse hacia unos árboles, mientras que el LS 4 sufrió daños menores pero aterrizó de manera segura. No se reportaron heridos.
- Approach to Hornberg: The LS 4 glider returned from a local flight and joined the landing pattern to runway 18 at Hornberg ahead of and slightly higher than the SF 25 motor glider.
- Converging flight paths: Both aircraft flew from opposite directions into the same final approach path to runway 18, with their descent rates adjusted so that both would reach a similar touchdown point.
- Lack of mutual sighting: Neither pilot had visual contact with the other aircraft in the final approach, and due to his position the glider pilot could not see the motor glider behind and below.
- Unnoticed close proximity: In the end of the final approach, the LS 4 descended from above into the flight path of the faster SF 25 approaching from behind, bringing the two aircraft into critical proximity without either pilot recognizing the conflict.
- Late go-around attempt: After multiple radio instructions from the flight supervisor to turn right and go around, the motor glider pilot initiated a go-around only at about 6–8 m above ground beneath the glider.
- Collision near touchdown: As the SF 25 accelerated and passed under the LS 4 about 15 m above ground, its fin struck the glider’s right wing trailing edge, tearing off the fin and bending the rudder.
- Mid-air collision: Following the collision the SF 25 became uncontrollable, landed hard, veered into adjacent trees and was destroyed, while the LS 4, only lightly damaged, remained controllable and landed normally on the airfield.